"Open cluster NGC 752 in Andromeda is old for such an object - 1.6 billion years. Its 100 member stars mainly shine between magnitudes 9 and 10. The exception is the magnitude 7.1 carbon star SAO 55138, which lies near the [middle right] of this image and forms a small but impressive triangle with two stars of magnitudes 8.9 and 9.6." - Astronomy Magazine - Spectacular Universe 2011
Other designations for NGC 752 include Caldwell 28 and Herschel 32-7.